The present invention relates to plastic cages for ball bearings.
A plastic cage for ball bearings is known (DD-PS 32 287) in which pockets are formed on one frontal edge, each pocket having an opening, limited by surfaces extending planeparallel and symmetrically to a radial line across the entire width of the wall of the cage, thereby determining the inside width of the pocket opening. The pockets are provided with spherically formed ball seat which, at high speeds, come into contact with the balls alternatingly at different places of their surface, while the bearing is in rotation. The contact area is furthermore reduced in its size because the pocket openings which, in its depth leads into the pocket, is formed in its entire radial extension so as to be open into the inside width of the pocket. Both will cause unsteady rotation of the cage with an especially unfavorable effect on bearing rotation and thus on the bearings themselves when rotating at high speeds.
It is an object of the invention to produce a cage which will not have these faults, and to design a cage in a shape which will result in contact with the ball always on the same pocket surface while the bearings are in rotation. It is a further object to provide at the same time a contact area between both parts as large as possible so as to ensure steady running of the cage, at very high speeds.